Cost avoidance is an important function of simulation in strategic planning. One of GM's cereal plants wanted to replace some low-speed packaging lines with multiple-head, higher-speed lines. Simulation showed that a bottleneck downstream would hold the new, high-speed lines to only a three percent improvement in productivity -- not enough to justify new equipment. Instead, it led plant operations to restructure the packing lines that ultimately increased plant capacity.
Witness software also saved GM $500,000 by not building an unneeded loading bay. The plant was planning a new loading facility with three bays for automatic transfer of product from silos to trucks and rail cars. This combined continuous-discrete process simulation was the first time the interaction and balance between production and truck schedules/loading duration were clearly understood, according to Beaverstock. Simulation showed that two bays would adequately handle the load, saving the company the cost of building the third bay.